Quake 4

Quake 4 cheat codes: 
Press the [Left Ctrl] + [Alt] + [~] during game play to
display the console window.

While in game press the [`] key to bring down the ingame console.
You can edit this key by going to
x:\Program Files\id Software\Quake 4\q4base\ and opening the file Quake4Config.
Look for line bind "`" "toggleconsole" and change "`" to the desired key
(i.e. bind "~" "toggleconsole").

Now enter the following cheats to activate the corresponding cheat function:
god                   - God mode
noclip                - No clip
notarget              - Invisibility
freeze                - Freeze everything
give all              - All weapons and ammo
give ammo             - Full ammo
map [map name]        - Load a map (see the list below)
benchmark             - Game benchmark
com_drawfps 1         - Show FPS
aviDemo               - Saves a demo of your playing to an AVI movie file
gfxinfo               - Graphics card infomation
r_gamma [0-3]         - Set gamma level
r_brightness [number] - Set brightness level
s_volume_db [number]  - Set sound volume (default is 0)
s_showlevelmeter 1    - Toggle sound level display (use 0 to disable this code)
g_showprojectilepct 1 - Toggle hit % to HUD (use 0 to disable this code)
killmonsters          - Kill all monsters
kill                  - Suicide
quit                  - Quit game

Map names:
Use one of the following values with the "map game/ [map name]" code:

Air Defense Base:          airdefense1
Air Defense Trenches:      airdefense2
Aqueducts:                 convoy2
Aqueducts Annex:           convoy2b
Canyon:                    convoy1
Construction Zone:         walker
Data Networking Security:  network2
Data Networking Terminal:  network1
Data Processing Security:  process2
Data Storage Security:     storage2
Dispersal Facility:        dispersal
Game/process1:             process1
Game/storage1:             storage1
Hangar Perimeter:          hangar1
Interior Hangar:           hangar2
MCC Landing Site:          mcc_landing
Nexus Core:                core1
Nexus Hub:                 hub2
Nexus Hub Tunnels:         hub1
Operation: Advantage:      mcc_1
Operation:Last Hope:       mcc_2
Perimeter Defense Station: building_b
Putrification Center:      putra
Recomposition Center:      recomp
Strogg Medical Facilities: medlabs
The Nexus:                 core2
Tram Hub Station:          tram1
Tram Rail:                 tram1b
Waste Processing Facility: waste

Model names:
Use one of the following values with the "spawn [object name]" code:
char_doctor
char_kane_strogg
char_marine
char_marine_fatigues
char_marine_medic
char_marine_tech_armed
monster_berserker
monster_bossbuddy
monster_failed_transfer
monster_fatty
monster_gladiator
monster_grunt
monster_gunner
monster_harvester_combat
monster_iron_maiden
monster_makron
monster_network_guardian
monster_repair_bot
monster_scientist
monster_sentry
monster_slimy_transfer


Weapon mod names:
Use one of the following values with the "spawn [object name]" code.
Note: You must already have the base weapon for the mod for it to
be of any use (enable the "give all" code first if needed).
weaponmod_hyperblaster_bounce1
weaponmod_lightninggun_chain
weaponmod_machinegun_ammo
weaponmod_nailgun_ammo
weaponmod_nailgun_power
weaponmod_nailgun_rof
weaponmod_nailgun_seek
weaponmod_railgun_penetrate
weaponmod_rocketlauncher_burst
weaponmod_rocketlauncher_homing
weaponmod_shotgun_ammo